Thread: Low cost BMS
View Single Post
Old 07-11-2011, 12:46 AM   #25 (permalink)
VW Polo EV
Join Date: Aug 2009
Location: Port Macquarie
Posts: 69
Thanks: 1
Thanked 10 Times in 9 Posts
Problems plagued the Volt Blochers (which is why I suspect they disappeared).
They had no form of fuse anywhere & they were permanently across the cells.
One of the two ICs it used was directly connected across the cell without a resistor divider. One particular brand of IC had a nasty habit of failing ON & then draining the battery to death as there was no safeguard to limit battery discharge & no indication it was happening either.
They also generated a LOT of heat from the TIP122 & the 5W resistor when they were shunting.
I still favour a system that disconnects the BMS electrically from the cells when the vehicle is off.
My current BMS has miniature relays on each board that switch off when the car is turned off.
Electric VW Polo

Last edited by ianbartie; 07-11-2011 at 03:15 AM..
  Reply With Quote